Light bleeding 2 weeks after period?

I started my period 2 weeks ago, it lasted 4/5 days as normal, but the last few days I've been very lightly bleeding with red/brown discharge. I've had slight cramps but nothing compared to when I'm on my period so not sure what it is? Just wondered if anyone else had the same and knows whether it's just old blood from my period or something else?

I've been on my period regularly as normal since last time I had sex so it's v unlikely that I'm pregnant.

Thanks!